Katana Dac by allo

Hello ladies and gents ,

as many of you heard , we have been working on a new DAC .

We asked ourselves how its possible to bring true HIFI sound to the RPI. We wanted a price point thats accessible to everyone while blowing away any DAC made by anyone under 1000$ .
Lets see if we succeeded

  1. DAC IC

First we chose a very capable IC , the ess9038q2m . This IC has excellent specs (theoretical THD+N at -120) and the analog stage (output) is left to the designer (more on analog stage below). One extra advantage of the ess9038q2m is DOP
Of course we used super caps and everything in audio path is film caps and thin film R.

  1. Clocks

Any delta sigma IC is very sensitive to the clocks (jitter). We used the "ultra low jitter clocks from NDK [url]NZ2520SDA[/http://www.ndk.com/en/products/search/clock/1190972_1433.html]. We also made sure that power was filtered by 2 LDOs in series along with a HF filter. Noise tested is in uV. Of course we also used buffers (that also has its power filtered 3 times…)
What we achieved is the lowest jitter ever (390fs)

  1. Analog stage

There are 2 kinds of analog stages , transfos and opamps. A lot of people swear by trans (with good reason) and others chose specific monolithic opamps. Still the consensus is that transfos are better as far as sound quality (but very expensive and bulky) and that opamps are better as far as THD+N numbers . If Opamps are used the quality of the PSU (opamps need dual rail 15V) is very important .

Still we felt that opamps CAN be better than transfos…

We concentrated a lot of efforts in this analog stage . You see , monolithic (integrated circuits) opamps suffer from the fact that not enough real estate is available on the silicon die .( excellent article sparkoslabs.com/audio-op-amps-g … bandwidth/ )

So our choice was ultimately to build a discreet opamp (with IV stage we got 6 of them) while feeding it from a DC/DC convertor that has filters on input (+ LDO) and filters on output (+ LDOs) and of a course a common mode choke (each rail has independent filtering) for a total noise thats lower than 1mV

However building an opamp is not a trivial task . What we did is partner with Sparkoslabs.com and used his excellent design (thx you Andrew the wizard) . One review of those opamps monoandstereo.com/2014/08/s … eview.html .

Each board is then hand trimmed (individually ) for DC offset (when board is warm to simulate conditions of a board that been running for at least 45 min)) and then programmed for THD+N compensation .

So in essence Katana dac is an excellent implementation of the Ess9038q2m in Master Mode (we are the first to do so)  , with a discreet stage made by 6 opamps running in[u] class A amplification[/u] . THD+N numbers (1Khz , 0 dbfs , a weighted ) at -112.75 !!! 

Pricing at 249$ (US) and 259Eur (tax included) Release date 17 of July

Sounds an interesting DAC allo :slight_smile:. Is it going to get a review on the Hamburg Soundcheck meeting, or is it too late for that now? I’m not attending, but will look at their feedback with interest.

We can only ship in a few days , we wont be able to make it in time

I believe you mentioned previously that you were also developing a new power supply (Nirvana) and a passive isolator.
Will those also be available at the same time?

Hello, can Katana supports native DSD or DOP?

How about use with Kali?

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the price includes pi and case?

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New isolator will be available for purchase with Katana

Price only includes the DAC (no RPI or casing)

Nirvana development is going, no news yet

Katana works with DOP but since its a master DAC no Kali is necessary (it does its own reclocking )

Thanks.

Allo has a separate casing already molded for this that can be purchased separately?

What rasp pi is it compatible? how about sparky? will it work on that device?

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Yes a new casing its necessary since this is a 3 stack DAC

  1. DAC board
  2. Opamp board (analog stage)
  3. Power and MCU

Compatible with all RPIs , not with Sparky since this is a master on the i2s bus (Sparky only allows slaves)

Do you mean the price includes DAC PCB and analog output PCB?

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BTW, what is Nirvana?

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Kali has ram to store I2S data to reclock, new DAC’s own Mclk can does as good as Kali? For me Kali is too good to abort.

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Katana DAC is made of 3 HATs. All are included in the price.

MCLK on master DAC is even better then Kali for the simple reason that mclk and buffers are only 2 cm away

There has ram buffer in Katana DAC PCB?

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Buffer is needed only on slave situation.

Master works differently , provide MCLK to DAC IC and lrck + bclk are provided to the CPU (from dac ic) asking only DATA to be sent back.

As such , the DATA is provided by RPI on each bclk (and we clean that rail using FB or R)

Master has the advantage of eliminating the RAM buffer and being immune to any noise (from CPU) on MCLK , BCLK and LRCK.

Only receiving channel is DATA (i2s)

Thank you for your clear explanation!

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is there an option to have a black acrylic for this katana? Screenshot_2018-07-05-14-27-18-639_com.google.android.apps.docs.jpeg

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Yes black will also be available but the offsets will be only silver.

are you going to send michaelangelo a review… or darko… or hanz beekyuzen.?

how much will the acrylic cost?

Michelangelo , Darko , Hans and about 17 more people will receive units for review (including Amir from audioreview , usually he does THD+N testing and more independently )

I hope that with so many reviews and diffrent points of view you can make a clear image on what Katana is.

Acrylic will be about 15-17$ with the offsets